Mitsubishi Electric RD77MS2 User Manual page 215

■Speed during continuous operation to torque control mode
The speed during the continuous operation to torque control mode is controlled with an absolute value of the value set in
"[Cd.147] Speed limit value at continuous operation to torque control mode" as command speed. When the speed reaches the
absolute value of "[Cd.147] Speed limit value at continuous operation to torque control mode", "Speed limit" ("[Md.119] Servo
status2": b4) turns ON.
n: Axis No. - 1
Monitor item
[Md.119] Servo status2: b4
In addition, "[Cd.147] Speed limit value at continuous operation to torque control mode" is limited with "[Pr.8] Speed limit
value". If the command speed exceeding the speed limit value is set, the warning "Speed limit value over" (warning code:
0991H) occurs, and the operation is controlled with the speed limit value.
The actual motor speed may not reach the command speed depending on the machine load situation during
the continuous operation to torque control mode.
■Current feed value during continuous operation to torque control mode
"[Md.20] Current feed value", "[Md.21] Machine feed value" and "[Md.101] Real current value" are updated even in the
continuous operation to torque control mode.
If the current feed value exceeds the software stroke limit, the error "Software stroke limit +" (error code: 1993H) or "Software
stroke limit -" (error code: 1995H) occurs and the operation switches to the position control mode. Invalidate the software
stroke limit to execute one-way feed.
■Stop cause during continuous operation to torque control mode
The operation for stop cause during continuous operation to torque control mode is shown below.
Item
"[Cd.180] Axis stop" turned ON.
Stop signal of "[Cd.44] External input signal operation
device (Axis 1 to 16)" turned ON.
All axis servo ON [Y1] turned OFF.
"[Cd.100] Servo OFF command" turned ON.
The current value reached the software stroke limit.
The position of the motor reached the hardware stroke
limit
PLC READY [Y0] turned OFF.
The forced stop input to Simple Motion module.
The emergency stop input to servo amplifier.
The servo error occurred.
The servo amplifier's power supply turned OFF.
*1 When the mode has switched from the speed control mode to the continuous operation to torque control mode, the mode switches to
the position control mode after switching the speed control mode once. Therefore, it takes the following time to switch to the position
control mode.
Switching time for the speed control mode + Switching time for the position control mode
Buffer memory address
2476+100n
Operation during continuous operation to torque control mode
The speed limit value commanded to servo amplifier is "0" regardless of the setting value of
"[Cd.147] Speed limit value at continuous operation to torque control mode". The mode switches
to the position control mode when "Zero speed" of "[Md.119] Servo status2" turns ON, and the
operation immediately stops. (Deceleration processing is not executed.)
The value of command torque is not changed. It might take time to reach the speed "0" depending
on the current torque command value.
The servo OFF is not executed during the continuous operation to torque control mode. The
command status when the mode is switched to the position control mode becomes valid.
An error (error code: 1900H, 1904H to 1907H, 1993H, 1995H) occurs. The mode switches to the
position control mode at the current position, and the operation immediately stops. (Deceleration
processing is not executed.)
When the operation immediately stops, the motor may start hunting depending on the motor
speed. Therefore, be sure not to reach the limit in high speed and not to turn OFF the PLC
READY.
The mode switches to the position control mode when the servo OFF (Servo ON of "[Md.108]
Servo status1" turns OFF) is executed.
(While the servo amplifier is servo OFF, even if the mode is switched to position control mode, the
servomotor occurs to the free run (The operation stops with dynamic brake).)
The motor occurs to the free run (The operation stops with dynamic brake.). (The mode is set to
the position control mode at the servo amplifier's power supply ON again.)
*1
*1
7 EXPANSION CONTROL
7.1 Speed-torque Control
7
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